THE RADIO WORLD

Hawke's Bay Tribune, Volume XVII, Issue 208, 17 August 1927, Page 3

THE RADIO WORLD

GOOD RECEPTION LAST FEW NIGHTS ’ NOTES IN GENERAL. (By ” Valve.”) A fair amount of static was prevalent at the beginning of last week, but this all cleared away and left almost perfect reception behind it, Friday night being particularly good. Daylight reception is good at this time of the year, and the relay of the races from Riccarton came in with excellent volume in most places. 2YA picked up and re-broadcast these results, thus enabling many listeners, who could not get 3YA direct, to receive the results comfortably. This re-broadcasting by 2YA is extremely welcome, especially to dealers; many of whom find that the direct reception from 3YA is practically drowned by interference from surrounding electric motors and similar sources of unwanted noise. ADVANTAGES OF HASTINGS STATION. The proposed Hastings station would improve things still more in this direction. The advantages that would come to local listeners from the erection of a station in Hastings are so obvious as to render writing them down here almost superfluous. The very first boon would be the virtual elimination of howling, as those people having sets which interefere in this respect would find the station so easy to tune in that their sets would be kept well away from the point where radiation commences. THE "WHOO-EE.” I am sure that ninety per cent, of these “birdies," as the Americans call them, really think that their interference only amounts to the mild whistle which they themselves hear, and are totally ignorant of the powerful ’’ whoo-ee,” that their tiny peep has developed into when heard by their neighbours. It should not be a difficult matter to tune without interfering. If it is, your set needs fixing. Even the most incompetent "Bill Muggins" could tune in a station that is situated at his back door without worrying others. On nights when old man static is aprowl, too, this station should be a great help, as nothing less than a thunderstorm in our own particular bit of country would cause reception to be too bad to be enjoyable. FINANCIAL HELP NEEDED. So I think it behoves every listener or prospective listener to help along the project, more particularly on the financial side, as it is only a matter of acquiring sufficient funds for the station to be on the air. RADIO DICTIONARY. A continuation of the radio dictionary is given herewith:— Condenser.—A device consisting of thin metal sheets separated by an insulating substance. One set of sheets is connected to the positive, and the other to the negative terminal of a source of current supply, the current flowing into the plates and charging them with electricity, which is stored and given up as required. Variable Condenser.—A condenser ii which one set of sheets is movable and overlaps the other without bringing the two sets into contact. By varying the extent of overlap, the capacity can be varied from zero to a maximum. In most variable condensers the two sets of plates are separated by air. Conductor.—Anything which permits the passages of, or serves to conduct an electric current.

Counterpoise.—A system of wires, near ground level, which forms a counterpart of an aerial, and which takes the place of, and virtually constitutes, an “earth.”

Coupling.—An arrangement of circuits, such that one of them can transfer electrical energy to the other.

Crystal Receiver.—ln last week’s notes a simple crystal set was described. This week the valve is discussed:—

The reason why a Triode is termed a valve may be easily guessed. The vacuum tube, or valve, has three essentials, the plate, the grid, and the filament. The plate and filament are connected to a local battery, the plate taking the positive, the filament the negative charge. The grid is charged by the alternating current, so that it is constantly changing from positive to negative. When positive, the grid, which is placed between the filament and the plate, assists the flow of electrons from filament to plate, these electrons being negative, and being attracted by the positively charged plate. When the grid is negative, it opposes the flow of the electrons, so that we have a constantly varying current flowing from filament to plate, the flow being controlled by the charge on the grid. A "hard” tube, one which contains the least air, allows electrons to flow with the least resistance. Such a tube makes a good amplifier. The "soft,” or less completely evacuated tube, retards the flow, and is only a moderate amplifier, but is a very efficient rectifier or "detector,” and is used as such.

Strength of reception with a crystal depends entirely on the strength of the alternating current, whereas with the valve we have a local battery, the alternating current being used to control the flow of direct current from this battery. Crystal Receiver.—A device for rectifying the oscillating current produced in an aerial or in a circuit coupled to the aerial circuit. It comprises a mass of crystals of carborundum or of some suitable mineral alloy which possess the property of allowing current impulses to pass in one direction, but not to any appreciable extent in the opposite direction. The circut is completed by bringing the "cat’i-whisker," or another crystal, into contact with the first. Crystal Receive.—A wireless receiver in which a crystal is employed to rectify the oscillating aerial current. PROGRAMMES FOR TO-NIGHT. I YA, AUCKLAND.—7.IS p.m.: News and information session. 7.30 to 7.45; Talk on "Physical Culture’*

by Mr Norman Kerr. 8: Chimes; relay of overture from Prince Edward Theatre, Br Geo. Poore conductor; contralto, Miss Chellberg; violin, Mr N. Watson; baritone, Mr Barry Coney; cornet, Messrs. Davies and Salthouse; boy soprano, Master D. Lunney; vocal, Mr F. Willoughby; weather report; relay from Prince Edward Theatre.

2YA, WELLINGTON.— Southland v. Wellington Rugby match.

3YA, CHRISTCHURCH.—6 p.m.: Children’s session by Uncle Jack. 7.15: Addington stock market reports and other market reports. 7.30: News and reports. 8: Chimes; relay of orchestral selections from Crystal Palace Picture Theatre Orchestra, under the direction of Mr. A. J. Bunz; bass solos, Mr F. R. Hawker; mezzo soprano soHos, Mrs Bingham Puddey; humorous recitation, Miss Kathleen O’Brien ; talk, Mr Donald Grant, M.A., “Austria” (the remnant of an empire) ; violin solos, Mr Bernard Barker; tenor solos, Mr Douglas Suckling. 4YA, DUNEDIN.—SiIent day. 2BL, SYDNEY. — 8 p.m.: G.P.O. clock and chimes. Broadcasters’ Topical Chorus, the Canterbury District Band (conductor, Mr Stan Nicholls) broadcast from Baker’s Hall, Campsie, Mr Harrison Allen (elocutionist), in selections from his repertoire, Miss Millie Hughes (soprano), Broadcasters’ all-sports expert will talk on boxing, Mr Raymond Beatty (basso), Sid and Molly Owen and Jack Nethersole in a medley of jazz, Mr Harrison Allen, Miss Millie Hughes and Mr Raymond Beatty, the Canterbury District Band, Miss Millie Hughes, Mr Raymond Beatty. Cec Morrison and his Gloomchasers broadcast from the ballroom of the Bondi Casino. During intervals between dances "Sun" news will be broadcast.

3LO, MELBOURNE. — 8 p.m.: Studio presentation of "Floradora" by the Victorian Opera Company; Studio Orchestra, “Merry Wives of Windsor” (Nichola); Signor Palmetto, tenor, "To the End of the World With You.” "I Passed by Your Window”; Studio Orchestra, "Molly on the Shore” (Grainger); the second act of "Rose Marie,” transmitted from His Majesty’s Theatre by permission of J. C. Williamson, Ltd. 4QG, BRISBANE.—B p.m.: From the Tivoli Theatre — Orchestral music, the Windsor Band. 8.30 p.m.: From the Studio. 9 p.m.: Metropolitan weather forecast; continuation of concert programme. WARNING TO RADIO ENTHUSIASTS. Wellington. August 16. The necessity for radio listeners-in to be careful was well illustrated on Saturday by the experience of a Wellington resident. He was listen-ing-in on a crystal set and using head-phones. Unconscious of any danger, he reached over to replace something that had got out of position in connection with a four globe radiator that had the current on. He was immediately transformed into a conductor for 230 volts Onlv when after seven or eight seconds the current was turned otf was he able to release the radiator. The case was referred to Mr George Laughlan. assistant general manager of the Electricity Department, He said the safe thing to do is to play safety. Don’t touch switches or other apparatus with rhe other hand on a tap or a range, or anything that gives an “earth.’’ Don't handle electrical apparatus while wearing head-sets. If evervthin" is in order nothing will happen, hut a fault exists very often where none is suspected.